JAPAN TAPPI JOURNAL January　2005

January　2005　Abstracts


Dirt Check on Pulping Process
　 - Dirt Control by Measuring It with "Dirt Counter" -

Hiroshi Nagai
OMRON Corporation IT Solution Div., Web Inspection Group

Dirt in the material of paper has been measured by checking dirt in the sample sheet that is made only for checking dirt.
By this way, the feedback timing is very late and also, it is very troublesome to make sample sheet, out of process.
Dirt Counter solved these problems by checking dirt directly in the slurry on the process. It is quite effective and convenient equipment, not only for DIP, but also for general KP.


The Development of the Polymer Rolls for Calender Machines

Atsuo Watanabe and Kenjiro Nakayama
Yamauchi Corp.

We have been developing and selling polymer rolls for various calender machines (SC, SNC and On machine multi- nip calendar) from 1987. We faced many problems from start such as “heat spots”, “crack propagations”, “abrasion”, “delaminations” and so on. For the counter-measure we improved both of cover materials and the adhesive strength, and decreased the inner stress of roll-covers fixed on steel cores.
On this paper we report the outline of the improvement and it’s results.


Operating Experience of Acid Treatment and Ozone ECF Bleaching

Masaki Fujii
Yatsushiro Mill, Nippon Paper Industries

Kraft pulp section of Yatsushiro mill consists of two fiber lines and both lines were converted to ECF bleaching sequence in 2003. Medium consistency ozone bleaching with an acid treatment (A stage) prior to ozone bleaching stage was introduced to the fiber line #2 for hardwood. This A stage is the first commercial application in Japan to prevent diffuser washer from scaling.
This report shows the mill experience of A stage and Ozone ECF bleaching.


Operating Experience of KURE 5 Paper Machine

Shirou Hirano
KURE Mill, OJI Paper Co., Ltd.

No.5 Paper machine at KURE mill, OJI Paper, which has been started operation as a fine paper machine in 1989, also now products LWC paper in response to the market changes. This machine was designated as the “model machine” in our company and we set up a project team to go about increase of productivity. As a practical measure, for the purpose of reducing deposits and web breaks, several equipment were installed.
This article introduces the experience of operating these equipment.


Operating Experience of MJ Turn Bar

Keiichi Sato, Kunio Kazama and Shigeharu Yamahata
Hachinohe Mill, Mitsubishi Paper Mills Limited

　Since NO.7 PM (Paper Machine) of Hachinohe Mill, Mitsubishi Paper Mills Ltd. began production in 1997, many kinds of paper products have been manufactured. Especially, woodfree light weight coated paper has such a good quality that the production of woodfree light weight coated paper is dramatically increasing. While we tried to speed up NO.7 PM in order to increase the production, we got a serious problem (release problem) which occurred at the release point of coated paper from the SymsizerR application roll. The release problem caused the unevenness of coated layer and prevented to increase the machine speed.
　　At last we decided to install “MJ Turn BarR” to NO.7 PM in order to improve the problem.　Then it was already introduced on October 2003 and it's been working well. “MJ Turn BarR” could make web releasing stability at the release point from the application roll and enable us to increase the machine speed.
　　In this paper we report about our operating experience of “MJ Turn BarR” that enabled us not only to keep the quality of woodfree light weight coated paper but also to increase the productivity.


Influence of Molecular Orientation on the Curling Phenomenon in Laminated Films
　- A Curl Control Method of "Communication Paper" -

Tadakazu Miyata
Advanced Technology Research Laboratory, Oji paper Co., Ltd.

Recently, plastic films have been widely applied to manufacture "communication paper", such as direct thermal films (or paper) and dye diffusion thermal transfer sheets. In these applications, the biaxially drawn films are used, and their molecular chain orientation causes "curl phenomena", particularly in laminated films.
We found that the curl-value (ΔK) of plastic films clearly related to the difference of the thermal expansion coefficients of each ply in laminated films, and the thermal expansion coefficient could be predicted by measuring the degree of molecular chain orientation (MOR-value) determined by the transmitted microwave intensity method.
Based on these findings, we propose that quantitative curl prediction is possible by employing an approximate formula derived from the lamination theory.


Development and Future of Waterproof Laminated Paper “Oper”

Senzo Yamaguchi
Komatushima mill, Nippon Paper Industries Co., Ltd.

“Oper”, which is a waterproof laminated paper, has been made by Nippon Paper Industries since 1988. “Oper” maintains the same characteristics as general papers, like “softness”, “printability”, “convertibility”. Now it is widely used in a commercial printing business and in a converted paper business.
At the early stage of development, “Oper” had some problems in quality, which were caused by the effect of roughness and moisture of base paper onto the surface morphology of laminate layers. We report here how we coped with these problems.
We also report the development of our new products, “The Poster”, and “Oper MDP”. “The Poster”, which is the product mainly used for posters, has improved ink drying property which was the strongly required property by a market. And “Oper MDP” was developed for full-color laser beam printer, which is one of the on-demand printing field which is remarkable growth field in recent years.
　　And we introduce our latest consideration to the environment.


Paper Pulp Raw Material Supply in the Future
　 - Research on Improvement of Production and Quality of Wood Biomass -

Takashi Hibino
Forestry Research Institute, Oji Paper Co., Ltd.

The supply of raw materials is a business base of the paper manufacture industry. It is necessary to aim at a production increase and a qualitative improvement of the wood biomass by the expansion of the afforestation area in the stable supply of the raw materials. Securing a suitable afforestation area will be expected to become difficult by the competition with the farmland acquisition that originates in the food problem. As a result, afforestation in a very bad environment with various environmental stresses is not avoided.
Oji Paper succeeded in the creation of an environmental stress resistant eucalyptus by using our original genetically modified technology. In addition, the genetic information database of the eucalyptus was as also constructed for the improving of the wood biomass. The wood formation mechanism of the eucalyptus is clarified, and it will aim at practical use for efficient production of the wood biomasses along with the stress tolerance in the future.
As a result, stable production of the wood biomasses becomes possible, and use as the recyclable resource for the wood biomass not to mention the paper pulp raw material to replace the fossil resource such as oil can be accelerated. In addition, it is expected that large-scale afforestation of the eucalyptus that has high carbon dioxide fixation ability becomes possible, and it contributes to the carbon dioxide absorption for the global warming prevention greatly.


Operational Experience of Power Boiler for PS Incineration

Kazunari Kumagai
Nippon Daishowa Paperboard Tohoku Co., LTD.

Since paper sludge (PS) generated in paper manufacturing has high water content and low calorific value, its utilization as heat source is not popular. On the other hand, waste tire is utilized partly only because reuse is restricted by particular application due to difficulty in treatment of wire contained in tire. Recently, treatment of waste tire becomes an issue of waste materials.
Incineration PS together with waste tire, but without auxiliary fuel (fossil fuel) support, has been satisfied. The incineration boiler can produce high temperature and high-pressure steam, and generate electric power of 14,000 kW in stable operation. Thus it contributes to resource and energy conservations, reduction of wastes and consequently utilization of wastes.
The incineration boiler was put in commercial operation since October 2003. Experience and establishment of the plant operation with regard to reduction of dioxin emission controlled by combustion temperature, turbine load control performed remarkably in the waste incineration boiler and maintaining the plant in stable and safe operation are described.


Operating Experiences of CL&K Removal System Using Ion-exchange Resin
　 - Chloride Ion & Potassium Ion Actual Operation Report of Removal System for Solution of 　　
Electrical Precipitator Ash at Recovery Boiler -

Youichi Kataoka
Niigata Mill, Hokuetsu Paper Mills, Ltd.

In the process of Kraft Chemical Recovery Cycle, Chloride (CL) and Potassium (K) entering with raw-material wood chip are gradually accumulated and concentrated during continuous operation. The plugging issue of carryover particles and dust in the Recovery Boiler is caused by decreasing melting temperature of dust along with increasing concentration of CL and K in the Black Liquor.
At the same time, fouling and corrosion at the super heater of Recovery Boiler is apprehended. To avoid above problem, proper portion of recovered Electrical Precipitator Ash was deserted from recovery cycle. In this manuscript, actual operation data from CL&K Removal System using Ion-exchange Resin developed and installed at Niigata Mill are introduced.


Operating Experience of RPF Boiler at Tomakomai Mill

Shunroku Matsubara
Tomakomai Mill, Oji Paper Co., Ltd.

Tomakomai mill, Oji Paper Co.,Ltd., has contributed to the cultural and economical development of Japan as the most important mill in Oji Paper since the establishment in 1910.
Today, Tomakomai mill is the largest newsprint mill in the world and continues to fulfill the obligation to provide stable supplies to the customers.
Oji Paper established the Environment Charter and is pledged to make further efforts to reduce its consumption of fossil fuel by promoting thermal recycling in which collected used paper and plastics which cannot be recycled are incinerated for energy.
In order to implement the plan, Oji Paper has installed a circulating fluidized bed boiler (CFB) at Tomakomai mill. It is the first high temperature and pressure boiler in the world, which uses RPF as the main fuel.
In this paper, the abstract of the RPF boiler is introduced and the operating experience is reported.


The Advanced Information System for Paper Roll Handling

Takahiro Shigematsu
Kushiro Mill, Nippon Paper Industries Co., Ltd.

This paper describes the modifications incorporated in the information system for the existing paper roll handling process. In order to share production, marketing and inventory information between the headquarters and each domestic mill, the paper roll tracking system was replaced in Kushiro Mill. Since the previous system lacked memory, communication bandwidth and expansion capacity, new PC system was introduced. It has successfully consolidated various products information into single database. The next phase which is to expand this service to each department by constructing company-wide LAN, has been introduced for two years, and promotes the new system capability to the headquarters.